Grate-bar



F. C.. STIMMEL.

GRATE BAR.

APPLICATION FILED IAN. 17,1918.

\m I III I Il II I I PIII-,I II I Iul- I. IIIII u .l N u 3 w s y I? HHH.- ,Il iffi I i L IIIIIIII III IIII -I I- Y I N\ m m\\ u w M www NEE mf. NIJ .Fw 2 WN 0. o mN/ U m. Im -II|-0I\mI. s N Y /o w I m m @mw/Omm I@ @w Q0: n.\O o \U o o Q O om O o ,1;

F. C. STIMMEL.

GRATE BAR.

APPLICATION FILED IAN. I7, 1918.

1,370,241 Patented Mar. 1, 1921.

UNITED STATES PATENT OFFICE.-

FREDERICK C. STIMMEL, OF CHATTANOOGA, TENNESSEE, .ASSIGNOR T0 THE CASEY- HEDGES CQ., 0F CHATTANOOGA,TENNESSEE.

Gamin-BAR.

Specification of Letters Patent.

Patented Mar. 1, 1921.

Application led January 17, 1918. Serial No. 212,168.

To all 'whom u may concern Be it known that I, FREDERICK C. STIM- MELa a citizen of the United States, residing at Chattanooga, in the county of Hamilton and State of Tennessee, have invented a new and useful Improvement in Grate-Bars, of which the following is a specification.

This invention relates to furnace grates, and more particularly to hollow grates through which air is blown into the fire.

Grate bars of this kind of unitary structure are objectionable for the reason'that if any portion of a grate bar becomes warped or burnt from the heat of the furnace the entire bar is rendered useless. Furthermore, since the upper portions of the grate bars are exposed to the heat of the fire while the lower portions are comparatively cool, the grate bars of unitary structure have a tendency to warp or buckle.

The objects of this invention are to produce a grate bar of this kind in which the parts-'which are most exposed to the heat of the fire are removably secured on the body or trunk portion of the grate bar, so that they can be replaced when burned or otherwisel damaged; also to so construct a grate bar of this kind that the heat of the lire will not cause buckling or warping 4of the grate bar; also to provide means bywhich the grate bars can be easily cleaned without interfering with the operation of the furnace; also to im rove the construction of grate bars of this kind in other respects hereinafter specified.

In the accompanying drawings Figure l is a top plan view of a grate bar embodying the invention, showing some of the top sections of the bar removed.

Fig. 2 is a side elevation thereof.

Fig. 3 is a fragmentary sectional view there of on line 3 3, Fig. 1, on an enlarged scale.

Fig. 4 is a fragmentary sectional plan view of a furnace having a grate provided with grate bars embodying the invention.

Fig. 5 is an end elevation of one of the grate bars.

Figs. 6 and 7 are transverse sectional eleations on lines 6-6 and 7-7 respectively,

ig. 8 is a perspective view of one of the removable top members of a grate bar.

Fig. 9 -is an elevation of one of the cap twyers for holding the top members on the trunk or body portions of the grate bars.

A represents the trunk or body portion of a grate bar which is hollow and is provided at its upper portion with a plurality of short upwardly extending tubular flanges or connecting tube L through which the air from ing a which is adapted to receive air under pressure. The trunk or body Iportion may be of any desired or suitable cross-section, that shown having a substantially flat lower portion and a transverselv rounded or arched'upper portion on which the tubular flanges a are formed. l

Each of the -grate bars is provided with an upper or top portion which constitutes a fire supporting bed andwhich is secured on the trunk or body portion Aand which preferably comprises a plurality of top sections These sections may be of any suitable shape, those shown including a substantially flat top portion b having downwardly depending sides and end or saddle portions b2 which are adapted to rest on the u per surface of the trunk or body portion-Y of the grate bar. The top sections are provided with a plurality of small holes or openings b3 for the dischar e of ashes from the fire, and a central air ischarge hole b* which registers with the tubular air discharge projections a of the body portions A, one of these top sections being provided for each of the projections a. The lower face of the top portion b of each section B is preferably. adapted to engage with an air discharge projection win such a manner as to hold the top sections in place on the hollow body portion of the grate bar. In the construction shown for this purpose each top section is provided with a downwardly extending annular bead or rid e b5 whichin the construction shown fits within a tubular extension a of the body portion of the grate, a gasket or washer b6 bein inserted between the top section and the tu ular extension to forni a substantially air tight connection. The top sections are preferably held in place on the body portion of the grate by means of cap twyers C provided with projections c having inclined faces adapted to engage with correspondingly inclined faces in the top sections. The cap twyers are provided with suitable air discharge openings, the cap twyers shown in the drawings being for that purpose provided with recesses or depressions ci in their peripheries betweenl the projections c. When the cap twyers are 1n position in the air dischar e holes) 1n the top sections, the depressions c form slot-shaped air discharge openings with the top sections through which air is blown into the ire ,fromthe hollow body Cportion of the grate cap twyers downwardly, thus securely holding the cap twyers in the air discharge hole t* of the top section and also pressing the top section against the seat formed in the upper portion of the air discharge projection a. An asbestos washer or the like d2 is preferably arranged between the' nut d and the bottom of the body portion A to form an air-tight connection. By means of the securing means described any of the top sections B can readily be removed from the rate bar by merely loosening the nut d. he top sections are spaced at short distances from each other, and by means of the securing device described, the top sections are free to expand and contract relativel to each other and to the body portion without causing arrily warping or buckling of the grate bar. he two, top sections arranged at the ends of the grate bar are preferably provided with extensions E projecting beyond the ends of the body portion of the grate bar and have downwardly extending flanges or parts e which are adapted to be bolted or otherwise secured to corresponding flanges e formed on the ends of the body portion A of the grate bar. The downwardly 'extending flanges c also serve to close the open ends of the hollow body portions of the grate bar.

Means are preferably provided for enabling the hollow body portions of the grate bars to be readily cleaned of any ashes or dust which may pass through the twyer openings. In the construction shown for this purpose a valve F .is preferably provided in the bottom of each grate bar. This valve closes a hole f in the bottom of the grate bar and is pivoted at 7 on the body portion of the grate bar. The valve F is normally held in a position to close the openings f in the body portion by means of a counter weight f2. When it is desired to clean the grate bar, it is only necessary to apply pressure by any suitable means to the weighted portion f2 of the valve to cause the valve to open. The air pressure within the hollow body portion of the grate bar will then force the dust or ashes out of the grate bar into the ash-pit. On releasing the pressure' on the weighted portion of the valve F, the valve will again be closed by the counterweight.

F ig. 4 shows a plurality of grate bars arranged in a furnace. .The grate bars are separated by the usual spacer plates or bars G which, in the construction shown, are provided with perforations or holes through which the ashes fall `into the ash-pit. Other spacer bars or plates may be `employed between the grate bars in place of those shown, andmeans other than the holes or perforations shown may be employed for disposing of the ashes, the perforations shown being particularly adapted for burning sawdust or other fine fuel.

The grate bars shown are simple in construction and have the advantage that any of the top sections can be readilyv replaced when burned out or otherwise damaged. By means of the construction shown the top sections are exposed to the heat of the fire and are free' to expand and contract without producing any warping or buckling of the body portion of the grate bars, which are exposed to comparatively little he'at, so that these parts will last indeinitely. vBy means of the valves F the grate bars can be cleaned whenever desired without in any way interferin with the operation of the grate.

I c aim as my invention 1. A grate bar comprising a hollow body portion having upwardly extending air outlet members, a lire supporting bed comprising a plurality of sections each of which is supported on one of said outlet members and which have downwardly depending saddle portions adapted to engage said body portion, and means for removably securing said sections to said body portion.

2. A grate bar comprising a hollow body portion having upwardly extending air outle't members, a fire supporting bed adapted to hold the ire entirely out of contact with said body portion and comprising a plurality of sections each of which is supported on one of said outlet members, each of said sections having an air discharge opening, cap twyers engaging said sections in said air discharge openings, and bolts extending through said body portion for securing said cap twyers and sections to said bodyportion'.

3. A grate bar comprising a hollow body portion having a plurality of air outlet openings, a fire supporting bed which has parts adapted to lit against the edges of said openings to form substantially airtight joints therewith, said bed having air disings in the body portion, cap twyers arranged in said openings in said bed, and means for securing said cap twyers to said body portion to hold said bed on said body portion.

4. A grate bar comprising a hollow body1 portion having a plurality of air outlet openings, a fire supporting bed which consists of charge openings registering with said openl a plurality of sections arranged end to end lengthwise of said body portion, each of Said sections being supported over one of said outlet openings and forming a substantially air-tight joint with the peripheries of said openings, said sections having air discharge openings registering with said openings in said body portion, and cap twyers arranged in said openings in the sections and secured to said body portion to hold said sections in place thereon.

5. A grate bar comprising a hollow vbody portion havingv air discharge openings spaced at intervals along said body portion, a plurality of fire supporting sections having flat upper surfaces forming a. substantially continuous fire supporting bed arranged above the body portion, each of said sections having an air discharge opening registering with one 4of said openings in said body portion and bein@ secured to the edges of the openings in said body portion, cap twyers arranged in the air discharge openings of said sections, and means extending through said body portion to secure said cap twyers to said sections and thereby hold said sections on said body portion.

6. A grate bar comprising a hollow body portion having air discharge openings and upstanding flanges su-rrounding said air discharge openings, a lire supporting bed consisting of a plurality of sections arranged end to end lengthwise of said body portion to protect said body portion against the action of the fire, said fire supporting bed having discharge openings through which the air from said,` body portion discharges to the fire, parts on said fire supporting bed adjacent the openings therein, said parts fitting into the upstanding flanges on said body portion, and means for releasably securing said sections independently of each other on said body portion, whereby any section may be removed without removing the other sections.

7. In a grate bar, the combination ofa hollow body portion having air discharge openings through the upper face thereof, upstanding flanges surrounding said openings, a fire supporting bed adapted to hold the fire out of Contact with said body portion. said fire supporting bed having air discharge openings therethrough which register with the openings in the body portion, projecting parts on the lower face of said bed, said parts engaging the flanges on saidv body portion to center the openings in said bed relatively to the openings in said body portion, downwardly depending saddle portions on said fire supporting bed, said saddle portions engaging the body portion, and means for removabliv securing said fire supporting bed to said body portion.

8. In a grate bar, the combination of a hollow body portion having air discharge openings through the upper face thereof, upstanding flanges surrounding said openings, a re supporting bed comprising a plurality of removable sections adapted to hold the fire out of contact with said body portion, each of said removable sections having an air discharge opening therethrough which is adapted to register with one of the openings in said body portion, projecting parts on the lower face of each of said sections and surrounding the opening therethrough, said parts engaging the up-` standing flanges on said body portion, downwardly depending saddle portions on each of said sections, said saddle portions engaging the body portion, and means for removably securing said sections to said body portion.

9. In a grate bar, the combination of a hollow body portion having air discharge openings through the upper face thereof, a fire supporting bed comprising a plurality of removable sections arranged end to end lengthwise of said body portion, the intermediately positioned sections each having a pair of downwardly depending end portions adapted to engage the body portion and the sections at the ends of the body portion each having an inner downwardly eX- tending end portion engaging the body p0rtion and an outer end portion which fits over and closes the end of the hollow body portion, means for securing said end portions to the hollow body portion, and means for removably securing each of said sections to said body portion.

10. In a grate bar, the combination of a hollow body portion having air discharge openings through the upper face thereof, upstanding flanges surrounding said openings, a fire supporting bed having downwardly depending saddle portions resting upon said body portion, parts on said lire supporting bed engaging the upstanding flanges on said body portion, said' fire supporting bed having openings therethrough adapted to register with the' openings in said body portion, cap twyers positioned in the openings in said fire supporting bed, means for removably securlng said cap twyers to said fire supporting bed and said fire supporting bed to said body portion, said body portion having an opening through its lower side, and a weight-controlled valve normally closing said opening.

W'itness my hand this 10 day of January,

FREDERICK C. STIMMEL. Witnesses:

WM. P. BRYANT, MARY Porn. 

